This invention relates broadly to carpet and upholstery cleaning machines used in the car wash industry. More particularly, the present invention relates to a non-vacuuming coin operated dry foaming carpet and upholstery cleaner for installation in the proximity of a conventional car wash bay adjacent a vacuum system. The invention is believed appropriately classified in United States Class 15, subclass 320.
As will be recognized by those with familiarity in the car wash industry, a wide variety of machines for cleaning the interior of customer vehicles exist. Many of these machines use simple vacuum suction, and some machines spray cleaning solutions concurrently with vacuuming. U.S. Pat. No. 4,194,262 issued to Finley on Mar. 25, 1980 discloses a machine which both vacuums and shampoos vehicle carpet and upholstery. An elongated hose extends from an upright, rigid enclosure to a customer operated hand tool. When the switch on the hand tool is activated, cleaning fluid is vigorously sprayed. Concurrently with the spraying of soap or cleanser, applied vacuum sucks spent cleaning solution away from the target area.
Numerous car wash devices of the latter type have been proposed. However, in my experience, the combining of cleaning fluid output with vacuum can lead to mechanical difficulties. Besides increasing the cost and bulk of the equipment, interference between the vacuum and spraying conduits can result. It has thus been suggested to separate the carpet cleaning function from the vacuuming function. For example, it is known to provide a foaming output through a brush associated with a coin operated machine so that the brush may be rubbed over the target area. As the brush is manipulated, the outputted foam results in a cleansing lather, and after the lather dries, the powder residue may thereafter be vacuumed away by a separate vacuum cleaner. In theory at least, the separate vacuuming system will be subjected only to dry or powdered wastes, and since it is not exposed to liquid soap, which can be corrosive, its own integrity may be preserved.
However, in known prior art devices, a problem exists in that too much liquid solution is usually dispensed. As a result, proper drying seldom occurs, and solution is deeply absorbed into the carpet or upholstery being cleaned. Since the applied solution seldom properly dries, corrosion and mildew can result. Additionally, such systems often leave the customer's vehicle with an undesirable smell of dampness. Even with the wet vacuum suction systems such as that described in U.S. Pat. No. 4,194,262, the volume of liquid cleaning solution discharged by such machines aggravates the dampness problem.
Hence the prior art has proposed the use of so-called dry foaming machines. In such machines a small quantity of liquid concentrate is emitted from a brush, and by appropriately agitating the area by vigorous scrubbing, dirt can thereafter vacuumed away as powder. However, I have found that conventional foaming applicators fail to correctly mix the foaming concentrate, because too much reliance is placed upon "spraying."
Known prior art dry foaming cleaning machines pump a high volume of shampoo through a cavity, and blow air through the cavity in an attempt to vigorously spray the target area. It has hitherto been thought that spraying is necessary to maintain proper foaming. Mixing typically occurs in a large cavity concurrently with spraying. I have found that vigorous spraying is unnecessary, because the user will put the brush in contact with that area to be cleaned anyway, and even a slowly dripping foam mixture will contact the area to be cleaned. Spraying also necessitates the use of too large a volume of solution, and since drying times are inadequate, dampness is unavoidable. Much of the cleaning concentrate which should be aerated tends to sink into the carpet. Dampness can result in corrosion and rust. In addition, such systems tend to waste precious cleaning concentrate, thereby inadvertently increasing operating cost to the car wash owner.
Hence I have proposed a cleaning system which vigorously and efficiently aerates the solution concentrate to maximize its "dry-foaming" ability, while minimizing the waste of liquid cleaning concentrate. My system, which readily facilitates dry-foam cleaning, minimizes the unnecessary spraying of liquid concentrate. The residue quickly dries to minimize the dampness problem.